CVE-2026-68192
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk33th percentile - higher than 33% of all known CVEs
Summary
In the Linux kernel's brcmfmac driver, there is a double-free vulnerability of DMA buffers. The function releasing scratch buffers does not null the pointers after freeing, so when called multiple times (e.g., during reset and removal) it leads to freeing the same allocation again.
Risk Assessment
This can lead to memory corruption, system crash, or potentially code execution by an attacker with influence over the driver.
Recommendation
Apply a Linux kernel update containing the fix that nulls the pointers after freeing the buffers.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: make release_scratchbuffers idempotent brcmf_pcie_release_scratchbuffers() frees the shared.scratch and shared.ringupd DMA buffers with dma_free_coherent() but does not clear the pointers afterwards, unlike the sibling release_ringbuffers() which NULLs commonrings/flowrings/idxbuf on release. Both the bus_reset .reset callback (brcmf_pcie_reset) and brcmf_pcie_remove() call release_scratchbuffers. When reset teardown has run before removal, remove's own teardown would call dma_free_coherent() a second time on the already-freed DMA allocation. NULL the pointers after free, matching release_ringbuffers(), so a later release observes that the allocation has already been released. This patch makes repeated sequential release safe; the reset-work lifetime is handled separately by the following patch. This issue was found by an in-house static analysis tool.